H Y M E N O P T E R A. 



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the suctorial Leptdoptera. This order has been con- 

 sidered a very natural one by all entomologists. Our 

 great author, Ray, was the first, who had any idea of 

 the group, which was named by him Tetraptcra or 

 Quadripennia ; but he included therein the Phn/- 

 gnnidcB and Ephemeridae. It was not, however, until 

 the tenth edition of the Systcma Naturae, that the 

 order was reduced to its present limits. In the 

 twelfth edition of the same work, three hundred and 

 fourteen species were described, but the number is 

 now vastly increased. The increase in the number 

 of genera has kept pace with that of the species, so 

 that, had it not been for the philosophical institution 

 of family groups, by Latreille, corresponding- in many 

 instances with the Linnsean genera, this and the other 

 orders of insects would have become a perfect chaos. 

 The structure of the parts of the mouth, as appearing to 

 indicate the essential habits, might be regarded as of 

 primary importance in determining the classification of 

 the insects ; but it is essential to bear in mind the fol- 

 lowing circumstances, which may have the effect of 

 proving that too great a weight ought not to be allowed 

 to these considerations. We have already said that the 

 Hymenoptcra in general feed upon the honey of flowers 

 hence, unlike the Coleoptera (in which some are pre- 

 daceons, others lignivorous, others herbivorous, and 

 others necrophagous) an uniformity in the mode of 

 nourishment exists ; the only variation consisting in 

 the employment of the sap exuding from the wounds 

 of plants, or the juices of fruits. If, indeed, certain 

 of the TcnthredinidcB (such as Tcnthredo scrophu- 

 larice) attack other insects, they form but an excep- 

 tion to a general rule, which they and some other 

 species infringe but rarely, and, as it would seem, only 

 when the excessive heat has dried up the supply of 

 honey. The ants and wasps also appear to offer ex- 

 ceptions to the rule, but it is not real, since as they 

 are often found upon flowers, of which they will suck 

 up the honey, it is presumable that this is their ordi- 

 nary food, and that if they destroy other insects, it is 

 only for the purpose of getting at the honey with 

 which the latter are gorged. Moreover, in the nests 

 of certain social wasps, and even in that of the Polistcs 

 Lichc'innna of Brazil, as observed by M. Auguste de 

 St. Hilairo, a quantity of cells, full of honey, have 

 been found, of which this distinguished traveller ate a 

 considerable quantity without experiencing any in- 

 convenience ; and the same has been observed in 

 respect to the honey found in the nests of Polistcs 

 g'i'/icri. The larger species of wasps will occasionally 

 a) tack raw meat in butchers' shops ; but this is of rare 

 occurrence, and can be only attributed to an occa- 

 sional diminution of their ordinary food ; indeed many 

 nests are too far distant from the habitations of man, 

 for the wasps which inhabit them to have recourse to 

 such a kind of food. In the same manner may be 

 explained the interesting instance of supposed instinct 

 exhibited by a wasp, recorded in some of the popular 

 works on natural history, which had captured a fly 

 which it was unable to" fly away with, owing to the 

 wind acting upon the wings of the latter, whereupon 

 it clipped off these wings and also the legs and then 

 flew off with it to devour it at leisure. Here it was 

 evident that the wasp had been prevented from obtain- 

 ing its usual supply of food, and that its instinct had 

 been sharpened by hunger. We were witness some 

 time ago of another equally interesting instance of 

 instinct exhibited by the same insect, which had dis- 

 covered some flies upon which it wished to make a 



meal, revelling upon excrement, which it was anxious 

 not to touch with its feet or wings in seizing its prey. 

 It approached, therefore, as near to one of the flies 

 as it could, and then with a swoop, which reminded 

 us of the flight of the hawk, darted upon the fly, and 

 carried it off without soiling itself. The ants, in like 

 manner, although some of them have the instinct to 

 secure in their nests entire colonies of aphides, do not 

 devour them, but merely lap up with their tongues 

 the saccharine fluid which they emit, and which is, in 

 fact, merely vegetable liquid slightly modified during 

 its passage through the body of the aphis. All other 

 species of hymenopterous insects observed killing, 

 wounding, or dragging along other insects, caterpil- 

 lars, or spiders, have been ascertained to be employed, 

 not in providing for their own support, but for that of 

 their offspring. The elongation of the parts of the 

 mouth of the Coleoptera, has been regarded as a 

 character indicating carnivorous appetites ; and hence 

 the same idea has been applied to those hymenoptera 

 which have the trophi, especially the jaws, elongated ; 

 but observation has proved that these species are 

 destined to carry heavier burdens than the others ; 

 their prey destined for their progeny is more weighty, 

 and they consequently need more powerful tools for 

 its transport. Now the Coleoptera have no work of 

 this kind to perform, and consequently the analogy 

 cannot be supported : and this observation, as it 

 appears to us, offers an interesting clue to the solu- 

 tion of the oft-debated question, why it should be 

 requisite to employ characters derived from so many 

 distinct organs in the natural classification of any 

 extensive group of animals, instead of deriving them 

 throughout the group from a single organ. 



In one order of insects, for instance, we find the 

 primary divisions founded upon variations in the con- 

 struction of the tarsi, whilst in other orders the struc- 

 ture of these parts is uniform. Thus it is only by 

 acquiring a perfect knowledge, not only of the struc- 

 ture, but of the habits of animals, that we can ever 

 hope to be made acquainted with the relative value 

 of this or that character, so as to be able to affirm, 

 with any thing like precision, that the one or the 

 other is of the greater importance ; and this happens 

 to be a question of considerable moment in respect to 

 the order at present under consideration, in which 

 some authors have distributed the families according 

 to their general structure, whilst others, and more 

 especially the Count de St. Fargeau, in the work 

 above mentioned, have regarded the various instincts 

 of the insects, as exhibited in their social, solitary, or 

 parasitic qualities, as of the highest value, although 

 these qualities may have but a very slight influence 

 upon the general structure of the insect; thus between 

 the humble bee and the parasitic humble bee ( Psithy- 

 rus\ there is so little general variation of structure, 

 that Mr. Curtis even doubts the propriety of their 

 generic separation, whilst St. Fargeau, looking at 

 their different instincts, places them in totally distinct 

 sections, regarding the slight modification of form in 

 the legs, (deflpndent, it is true, upon the pollinigerous 

 or parasftic habits of the different insects), of far higher 

 importance than that entire variation of structure 

 which separates such families as the working bees and 

 wasps, which are united together by the common tie 

 of sociality. As regards the order of insects in ques- 

 tion, this mode of viewing their classification has 

 hitherto been too much neglected to enable us to fol- 

 low it out in a work like the present, which ought to 



